A beginner's guide to streaming with low latency

Many of us are aware of the delay when it comes to video data transmission.

What exactly is low latency? Do you need to reduce latency on all of your live occasions? We'll answer this question and more with this article.

An introduction to low latency

Low latency is the minimal delay for video data to transfer from the player onto the screens of your viewers.

The lower time to transmit data makes for an excellent watching experience as well as facilitating interaction. Here's the thing to get low latency: it is necessary to sacrifice less resolution or better quality video.

Luckily, no live event requires low latency.

It is essential in live streaming events to provide a live interaction or viewing experience. In these cases the audience is expected to see what's going on or participate in the live stream during the course of the event. Therefore, you cannot afford to pay for the high-latency requirements and you will need to stream with lower than 4K video resolutions.

Although this is low-latency streaming in a nutshell, let's dig deeper into the specifics of what it takes and how to achieve it.

What is low latency

When translated, latency literally refers to a delay in transmission.'

For the purposes of video latency, this means the length of time it takes from the video captured from your camera to play on your players' viewers.

Thus, low latency means lower time spent in moving video data between point A (your headquarters for streaming) and to the point of B (your your audience's members).

A high latency will take longer for transmission of video data from live streamer's audience to the.

What constitutes as a low latency?

In accordance with industry standards high-quality live streaming is 10 seconds and under while streaming broadcast tv ranges from 2- 6 minutes. Depending on your use case you may even attain ultra-low latency which lies between 2 - 0.2 seconds.

What is the reason you're looking for the lowest latency when streaming video? You don't need the same level of latency for each live stream that you host. But you do need it for all interactive live stream.

The key here is the amount of interaction that your live event needs.

If your event is, for example auctions live, you'll need streaming with low latency. Why? In order to make sure that every interaction is on time - and without delay, as this could give some participants an unfair advantage.

We'll look into more examples of these usage cases later.

What are the times you require streaming that is low-latency?

The greater participation in live streaming your event demands the less transmission time you need. This way, attendees can take advantage of the event in real time without any delay.

These are some instances where you'll require streaming with low latency:

• Two-way communicationssuch as live chat. This includes live events where Q&As take place.
• Experiences in real-timeis essential such as with online games.
• Participation of the audience is required. This is the case, for instance, when it comes to cases of bets on sports, as well as live auctions.
• Real-time monitoring. For example, searches and rescue operations, military-level bodycams, and baby and pet monitors.
• Remote operation which require constant connection between distant operators and machinery that they are in control of. Example: endoscopy cameras.

When should you use low-latency streaming?

To summarize the various scenarios which we've previously discussed It is necessary to have low latency streaming when you're streaming any of the following:

• Content that is time-sensitive
• Content that requires real-time audience interaction and engagement

Why not utilize the lowest latency possible for all of your videos? In the end, the less delay your content has in being seen by your viewers, more effectively, right? Well, not exactly. Low latency does comes with drawbacks.

The disadvantages include:

• Low latency compromises video quality. The reason: high video quality slows the transmission workflow due to its large file size.
• There's little buffered (or pre-loaded) content available in this line. There's not much space for error should there be a network issue.

In the event of live streaming an online streaming service such as quickly pre-loads some content before broadcasting to viewers. This way, when there's an issue on the network, it will play the buffered video, which allows the network-caused slowdown to be remediated.

As soon as the network issue is resolved The player will download the top quality possible video. However, all this happens behind the scenes.

The result is that viewers receive the same high-quality, uninterrupted replay experience unless, obviously, a significant error on the network occurs.

If you choose to go with low latency however it's not as much playback video to be prepared by the player. It leaves little chance of error when an issue with your network occurs out of the blue.

However, the high level of latency can be beneficial in certain instances. In particular, the longer time lag gives producers the opportunity to block vulgar content or inappropriate language.

Similarly, in cases where you can't compromise with the quality of video broadcasting, you can increase the delay by a small amount to ensure an excellent viewing experience, as well as allow to adjust for errors.

How is latency measured

With the definition of streaming with low latency and its applications off the table, let's see how you can measure it.

Technically, low latency is defined by the unit the round-trip duration (RTT). It refers to the length of amount of time required for a packet to travel from A to B and to reach back the source.

For calculating this number, an effective way is to include video timestamps and ask a teammate to watch the live video.

Have them look for the exact time frame that will appear on the screen. Next add the timestamp's duration from the time the viewer got the exact image. That will calculate your time of arrival.

Alternatively, ask a teammate to follow your stream and record a particular signal when it appears. Take note of the moment you played the cue in the live stream and the time your designated viewer saw the cue. It will provide you with time, although not as precise as the method above. It's still enough for a rough idea.

How can you reduce the latency of video?

What are the steps to achieve lower latency?

The truth is that there are a variety of factors that impact video latency. From encoder settings to the streamer you're using, several factors have a role to play.

So let's examine these aspects and how you can optimize them for reducing streaming delay while also ensuring the quality of your videos don't suffer a significant hit:

• Internet connection form. The internet connection affects data transmission rates and speed. That's the reason why Ethernet connections are more suitable to stream live than WiFi and cellular data (it's more beneficial to keep those as your backups though).

• Bandwidth. A higher bandwidth (the amount of data which can be transmitted at one moment) means less congestion and faster internet.

• Video file size. Bigger sizes require more bandwidth in transferring from one point to B, which increases time to transfer and vice versa.

• Distance. This is how far away you are from your Internet source. The more close you are to the internet source, the faster the video stream you upload will be transferred.

• Encoder. Select an encoder that helps to keep your latency low by communicating signals directly from your device to the receiving device as quickly a period of time as is possible. Make sure the one that you choose works with your streaming service.
• Streaming protocol is the protocol used to transfer your data packets (including audio and video) through your laptop to viewers' screens. To achieve low latency, it is necessary to choose a streaming protocol that reduces the loss of data while also introducing lesser latency.

We'll now look over the protocols for streaming that you could choose from:

• SRT: This protocol effectively sends video of high quality over long distances while maintaining very low latency. However, since it's relatively new, it's still being adopted by tech including encoders. How can you solve this problem? Combine it with another protocol.

• WebRTC: WebRTC is an excellent video conferencing tool but it does have some compromises on video quality since it's focused on speed mostly. The problem, however, is that a lot of video players aren't compatible with it since it needs the creation of a complicated setup to allow to be deployed.
• High-latency HLS is great for streaming with low latency of up 2-seconds. This makes it perfect for live streaming with interactive features. It's an undeveloped specification and it's not yet supported for implementation. development.
  

Live stream with low latency

The streaming of low latency is achievable with an extremely fast internet connection, a high capacity, best-fit streaming protocol available with an encoder that is optimized.

What's more is that closing the gap between yourself and the internet, and using lower-quality videos can be helpful.